Alginate Microcapsules Research Articles

A Functional Bread Fermented with Saccharomyces cerevisiae UFMG A-905 Prevents Allergic Asthma in Mice

BackgroundThe administration of probiotics has been shown to be beneficial in asthma. The administration of Saccharomyces cerevisiae UFMG A-905 prevented asthma development. Traditionally, probiotics are administered using dairy-based matrices, but other vehicles (e.g., fruit juices, biscuits, candies, and breads) can be used. ObjectivesThis study aimed to assess the effect of bread fermented with S. cerevisiae UFMG A-905 in asthma prevention. MethodsThree breads were produced: fermented with commercial yeast, fermented with S. cerevisiae UFMG A-905, and fermented with S. cerevisiae UFMG A-905 with the addition of alginate microcapsules containing live S. cerevisiae UFMG A-905. Characterization of the microbial composition of the breads was performed. Male Balb/c mice were sensitized and challenged with ovalbumin. Breads were administered 10 d before the first sensitization and during sensitization and challenge protocol. Yeast fecal count, in vivo airway hyperresponsiveness, and airway and lung inflammation were assessed. ResultsIn UFMG A-905 bread, there was an increase in yeast number and a decrease in total and lactic acid bacteria. Animals that received S. cerevisiae UFMG A-905 fermented bread with microcapsules had a significant increase in yeast recovery from feces. S. cerevisiae UFMG A-905–fermented breads partially reduced airway inflammation, decreasing eosinophils and IL5 and IL13 concentrations. When adding microcapsules, the bread also diminished airway hyperresponsiveness and increased IL17A concentrations. ConclusionsS. cerevisiae UFMG A-905 was able to generate long-fermentation breads. Microcapsules were a safe and viable way to inoculate the live yeast into food. The administration of breads fermented with S. cerevisiae UFMG A-905 prevented asthma-like characteristics, being more pronounced when the breads contained microcapsules with live yeast.

Comparison of the Adsorption and Desorption Dynamics of Biological Molecules on Alginate Hydrogel Microcapsules-The Case of Sugars, Polyphenols, and Proteins.

The aim of this work was to analyze and compare the adsorption and desorption processes of carbohydrates (glucose as a model molecule), polyphenols (gallic acid as a model molecule), and proteins (bovine serum albumin, BSA as a model molecule) on alginate microcapsules. The adsorption and desorption processes were described by mathematical models (pseudo-first-order, pseudo-second-order, and Weber-Morris intraparticle diffusion model for adsorption, and first-order, Korsmeyer-Peppas, and the Higuchi model for desorption) in order to determine the dominant mechanisms responsible for both processes. By comparing the values of adsorption rate (k2) and initial adsorption rate (h0) based on the pseudo-first-order model, the lowest values were recorded for BSA (k1 = 0.124 ± 0.030 min-1), followed by glucose (k1 = 0.203 ± 0.041 min-1), while the model-obtained values for gallic acid were not considered significant at p < 0.05. For glucose and gallic acid, the limiting step of the adsorption process is the chemical sorption of substances, and the rate of adsorption does not depend on the adsorbate concentration, but depends on the capacity of the hydrogel adsorbent. Based on the desorption rates determined by the Korsmeyer-Peppas model (k), the highest values were recorded for gallic acid (k = 3.66236 ± 0.20776 g beads/mg gallic acid per min), followed by glucose (k = 2.55760 ± 0.16960 g beads/mg glucose per min) and BSA (k = 0.78881 ± 0.11872 g beads/mg BSA per min). The desorption process from alginate hydrogel microcapsules is characterized by the pseudo Fickian diffusion mechanism.

Sustainable biologically self-healing concrete by smart natural nanotube-hydrogel system

Biologically self-healing concretes are generally composed of immobilized or encapsulated bacterial spores and nutrients. The efficiency of this self-healing approach depends on the effective protection and storage by the carriers. This report describes a novel sustained-release strategy for the improved self-healing function and microcapsule resistance to the cement environment. Halloysite clay nanotubes (HNTs) loaded with the common microbiological nutrient, yeast extract (YE) were encapsulated in calcium alginate microcapsules alongside Bacillus pseudofirmus spores. The encapsulation of the YE-loaded HNTs improved the resistance of the microcapsules to the cement environment, improved the microcapsule-cement interface, while successfully retaining the nutrients after direct contact with the cement pore solution. The self-healing system effectively healed artificial concrete cracks compared to control samples, reducing the crack water tightness by over 95%, and improved the flexural strength regain by approximately 75% after 56 days of wet-dry incubation. The sustained-release mechanism considerably improved the self-healing performance.

The Efficacy of Nile Tilapia Vaccination by Formalin killed Streptococcus agalactiae Encapsulated in Alginate Microcapsules

Nile tilapia is one of the major farmed fish that is often infected with Streptococcus. Oral vaccination is the most preferable technique, but the antigen is usually degraded by gastric juice. Encapsulation by alginate could be effective in protecting the antigen. The aim of this study was to assess the effectiveness of vaccinating Nile tilapia using formalin-killed Streptococcus agalactiae encapsulated in alginate. The average diameter of fabricated microcapsules was 500±20 μm, with 86% encapsulation efficacy. Fish were then divided into four groups (30 fish per group): group A: fish vaccinated by alginate microcapsules covered by formalin-killed cells (FKC), group B: fish vaccinated by non-covered FKC, group C: fish fed with empty alginate microcapsules and group D: fish feed with commercial pellets as control group. All groups were treated for 14 days and then fed with commercial pellets. Blood samples were collected on days 7, 14, 21, and 28 days post-vaccination. Bactericidal activity, lysozyme activity and serum antibody titer were significantly elevated in group A (p&lt;0.001) compared to other treated groups. Then, gene expression analysis was performed at 29 days post-vaccination to evaluate the expression of main immune contributors such IgM, IgT, TCR β, CD4, CD8α, IL 1β, IL 8, IFN 1, and TNFα. The analysis showed significant upregulation of all tested genes in group A compared to other treated groups (p&lt;0.001). Lastly, a challenge test was done on day 30 post-vaccination by injecting 4.6×106 CFU mL−1 of virulent S. agalactiae. The relative percent of survival (RPS) were 92± 2%, 48± 5% and 4± 3% for groups A, B and C respectively. The obtained result indicated that alginate encapsulation provided antigen protection due to its higher immunogenicity compared to non-covered vaccine. Hence, the fabricated vaccine could be incorporated with food and orally administered to Nile tilapia to prevent S. agalactiae infection.

Effect of Microencapsulation on the Antidiabetic and Antioxidant activities of Elaeocarpus tectorius (Lour.) Poir. Leaf extracts- An In vitro study

Microencapsulation is a novel, cost-effective technique that helps in protecting the bioactivity of plant extracts. The current study is aimed to prepare chitosan-coated sodium alginate microcapsules containing Elaeocarpus tectorius leaf extracts and to study its antioxidant and antidiabetic properties using in vitro assays. The ethanolic extract of E. tectorius was subjected to UV-VIS and FTIR analysis. The extracts were then subjected to microencapsulation using chitosan and sodium alginate. The synthesized chitosan-sodium alginate microcapsules were characterized using FESEM analysis. Further, the antioxidant and antidiabetic activities of the prepared microcapsules and crude extracts were assessed using in vitro assays. The UV-VIS and FTIR analysis of the leaf extracts revealed the presence of functional groups of phenolics, flavonoids and proteins. The microcapsules exhibited good antidiabetic potential through the inhibition of α- amylase and α- glucosidase enzymes. The antioxidant assays revealed that the microcapsules exhibited significantly higher antioxidant potential compared with the crude extracts. The chitosan-sodium alginate microcapsules containing Elaeocarpus tectorius leaf extracts could be used as an alternative to synthetic antidiabetic drugs and as a rich source of antioxidants.

Design of Functional Yogurts with Microencapsulated Biologically Active Compounds

The development of functional foods providing health benefits above the basic nutritional needs is of great interest to the food industry. This research aimed to: design functional yogurts with agave inulin and extracts from propolis, rose petals and Spirulina platensis; observe the physicochemical and microbiological changes during storage at 4°C for 21 days; evaluate the sensory characteristics of the new functional products. Three kinds of calcium alginate microcapsules (agave inulin + ethanolic propolis extract; agave inulin + ethanolic propolis extract + rose petals extract; agave inulin + ethanolic propolis extract + Spirulina extract) were prepared and applied in yogurts before the coagulation. During the storage, pH in all experimental groups gradually decreased (reaching values between 3.94 and 4.02 on the 21st day), which corresponded to the increasing titratable acidity (reaching values from 94.17°T to 108.78°T on the 21st day). The application of microcapsules did not affect the coagulation process and number of lactic acid bacteria in yogurts until the end of storage period. To the best of our knowledge, this is the first study to investigate the application of agave inulin, propolis, rose petals and S. platensis extracts in microencapsulated form in traditional Bulgarian yogurt in order to obtain a dairy product with enhanced functional properties. Keywords: Functional foods, Yogurt, Microencapsulation, Propolis, Rose petals, Spirulina platensis

Cytoprotective alginate microcapsule serves as a shield for microalgal encapsulation defensing sulfamethoxazole threats and safeguarding nutrient recovery

Microalgal encapsulation technology is expected to broaden more possibilities for employing microalgae for upgrading conventional biological wastewater treatment. However, only limited and fragmented information is currently available on microalgal encapsulation and pollutant removal. It is ambiguous whether it hold potential for wastewater treatment. Particularly, it remains to be determined whether this technology can provide more possibilities in harsh sewage environments. Here, potential of encapsulated technology to recover nutrients from wastewater was examined, simultaneously compared with commonly adopted suspended system. Results indicate the encapsulated microalgal system showed outstanding advantages in nutrient recovery and defense against antibiotic threats. Moreover, by examining the cellular oxidative stress response and changes of the photosynthetic system, the encapsulated system exhibited potential cytoprotective advantages to microalgal cells for defensing antibiotic threats. Molecular dynamics simulation revealed that the differences among superficial aggregation between the nutrients’ ions and molecular sulfamethoxazole on the cross-linked alginate microcapsule surface dominated the nutrient recovery and cytoprotective functions. Ultimately, the molecular nature of pollutants was found to be the most critical aspect for predicting application of this microalgal microcapsule. Cytoprotective systems created with alginate microcapsules can potentially handle more diverse threats with a single type of surface charge in their outermost layer.

Alginate Microcapsules Loaded with Eryngium billardieri Extract and Its Application in Apple Juice

Fruit juices can be enriched with plant extracts to enhance the nutritional and biological value of the product. Plant extracts are rich sources of bioactive compounds such as polyphenols with potential health benefits for consumers. In the present study, alginate microcapsules containing Eryngium billardieri (EB) extract (derived from aerial parts) were prepared and incorporated into apple juice. EB extract as nonencapsulated (NE), encapsulated (E) in microcapsules, and the combination of nonencapsulated + encapsulated (NE + E) at different concentrations of 1, 3, and 5% (w/v) were added to apple juice. These sample groups were stored at 4°C, and quality characteristics were evaluated for 21 days with a week of regular intervals. The results showed that the prepared microcapsules were spherical shaped with a size of 150–170 μm. The highest (75.12%) and the lowest (70.63%) encapsulation efficiency (EE) on the first day of storage were obtained in microcapsules containing 5% and 1% extract, respectively. EE decreased during storage time, and the lowest EE (65.25%) was observed in samples with 1% extract on day 21. Incorporation of E and NE + E extract improved total anthocyanin, total phenolic content, total flavonoid content, and antioxidant activity of apple juice due to the protective effects of the encapsulation on polyphenol compounds in the extract. After 21 days of storage, the highest (10.21%) and the lowest (5.85%) ascorbic acid contents were observed in samples with 5% NE + E t and control samples, respectively. Addition of EB extract to apple juice prevented the growth of yeasts and molds till day 7, and encapsulation of extract could enhance inhibitory activity. In terms of sensory acceptability, apple juices containing encapsulated extract received higher scores by panelists as a result of masking the unpleasant color and flavor of the extract. These results indicate that the application of EB microcapsules has potential for use in the food industry.

Preparation of a Lactobacillus rhamnosus ATCC 7469 microencapsulated-lactulose synbiotic and its effect on equol production.

Equol is a highly active product of soy isoflavones produced by specific bacteria in the human or animal colon. However, equol production is influenced by differences in the gut flora carried by the body. Our previous research has shown that a synbiotic preparation comprising the probiotic Lactobacillus rhamnosus ATCC 7469 and the prebiotic lactulose can enhance equol production by modulating the intestinal flora. Nevertheless, the harsh environment of the gastrointestinal tract limits this capability by diminishing the number of probiotics reaching the colon. Microencapsulation of probiotics is an effective strategy to enhance their viability. In this study, probiotic gel microspheres (SA-S-CS) were prepared using an extrusion method, with sodium alginate (SA) and chitosan (CS) serving as the encapsulating materials. Scanning electron microscopy (SEM) was employed to observe the surface morphology and the internal distribution of bacteria within the microcapsules. The structural characteristics of the microcapsules were investigated using Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Furthermore, the thermal stability, storage stability, probiotic viability post-simulated gastrointestinal fluid treatment, and colon release rate were examined. Finally, the impact of probiotic microencapsulation on promoting equol production by the synbiotic preparation was assessed. The results indicated that the microcapsules exhibited a spherical structure with bacteria evenly distributed on the inner surface. Studies on thermal and storage stability showed that the number of viable cells in the probiotic microcapsule group significantly increased compared to the free probiotic group. Gastrointestinal tolerance studies revealed that after in vitro simulated gastrointestinal digestion, the amount of viable cells in the microcapsules was 7 log10 CFU g-1, demonstrating good gastrointestinal tolerance. Moreover, after incubation in simulated colonic fluid for 150 min, the release rate of probiotics reached 93.13%. This suggests that chitosan-coated sodium alginate microcapsules can shield Lactobacillus rhamnosus ATCC 7469 from the gastrointestinal environment, offering a novel model for synbiotic preparation to enhance equol production.

Influence of metronidazole loaded into silver nanoparticle microcapsules on efficacy of alginate gel in correction of structural and functional disorders of dental support apparatus in rats with periodontitis

Objective: To evaluate the effect of metronidazole loaded into silver impregnated alginate microcapsules on the structural and functional disorders of the dental support apparatus in periodontitis. Material and methods. The studies were carried out on 30 white male rats randomly divided into two groups. Comparison group — 15 animals with an experimental model of periodontitis, which underwent applications of a gel containing microcapsules without additional loading with active substances. The experimental group included 15 animals with periodontitis, which were subjected to applications of gel with microcapsules containing metronidazole on inflamed gums. To assess the morphological changes in the supporting apparatus of the tooth, the mandible was taken with subsequent histological examination. Results. Results. Application of a gel containing microcapsules with silver nanoparticles loaded with metronidazole on the gums of animals with periodontitis leads to partial reduction of structural disorders. Thus, local disorganization of the fibers of the circular ligament of the tooth in the experimental group was observed only 5 cases, signs of limited bone loss — in 2 cases out of 15. In the comparison group, all 15 animals showed bone resorption and in 13 of 15 cases there was diffuse fiber alteration throughout the circumferential ligament of the tooth. Conclusion. The inclusion of alginate microcapsules with silver nanoparticles metronidazole leads to a significant decrease in destructive processes occurring in the near-tooth tissues during periodontitis.

BDE-47-mediated cytotoxicity via autophagy blockade in 3D HepaRG spheroids cultured in alginate microcapsules

Polybrominated Diphenyl Ethers (PBDEs) are a major class of brominated flame retardants, and their widespread use has led them to be considered contaminants with emerging concern. PBDEs have been detected in the indoor air, house dust, food, and all environmental compartments. The congener BDE-47 (2,2′,4,4′-tetrabromodiphenyl ether) is the most prevalent, and hepatotoxicity, neurotoxicity, immunological changes, endocrine disruption, and genotoxic potential have been related to its exposure. Although the BDE-47 molecular toxicity pathway is directly related to intrinsic apoptotic cell death, the role of autophagy in BDE-47 toxicity remains unclear. In this context, three-dimensional cell culture has emerged as a good strategy for the replacement of animals in toxicological testing. Here, we used HepaRG spheroids cultured in alginate microcapsules to investigate the role of autophagy in BDE-47-mediated hepatotoxicity. We developed mature and functional HepaRG spheroids by culturing them in alginate microcapsules. Histological analysis revealed that HepaRG spheroids formed an extracellular matrix and stored glycogen. No apoptotic and/or necrotic cores were observed. BDE-47 showed concentration- and time-dependent cytotoxicity in HepaRG spheroids. In the early exposure period, BDE-47 initially disrupted mitochondrial activity and increased the formation of acid compartments that promoted the increase in autophagic activity; however, this autophagy was blocked, and long-term exposure to BDE-47 promoted efficient apoptotic cell death through autophagy blockade, as evidenced by an increased number of fragmented/condensed nuclei. Therefore, for the first time, we demonstrated BDE-47 toxicity and its cell pathway induces cell death using a three-dimensional liver cell culture, the HepaRG cell line.

Microencapsulation and Peptide identification of purified bioactive fraction from spirulina protein hydrolysates with dipeptidyl peptidase IV (DPP-IV) inhibitory activity

The growing worldwide occurrence of type 2 diabetes mellitus (T2DM) necessitates the development of effective treatments. This study presents a comprehensive investigation into the inhibitory effect of trypsin-digested Spirulina protein hydrolysate (SPH) on the dipeptidyl peptidase IV (DPP-IV) enzyme, responsible for deactivating incretin hormones that stimulate insulin secretion. Following purification through hydrophobic interaction chromatography, the DPP-IV inhibition potential was enhanced, achieving a level of 74.20% ± 5.78%, with a half-maximal inhibitory concentration (IC50) value of 0.46 ± 0.16 mg/ml. By subsequently encapsulating the purified SPH within alginate and chitosan microcapsules, a controlled and sustained release profile of bioactive peptides was achieved while retaining their DPP-IV inhibitory activity. The encapsulation process exhibited an efficiency of 86.30% ± 0.16% and an efficacy of 80.65% ± 0.16% for SPH loading. Further analysis via LC-MS/MS revealed a potent peptide, GPNYASSER, derived from phycocyanin, exhibiting an IC50 value of 0.358 ± 0.188 mM. Beyond the search for specific peptides displaying strong DPP-IV inhibitory properties, the integration of SPH as function components for Type 2 Diabetes Mellitus (T2DM) management holds significant promise as a pathway for long-term preventive strategies.

ECM-based bioactive microencapsulation significantly improves islet function and graft performance.

Microencapsulation is a promising strategy to prolong the survival and function of transplanted pancreatic islets for diabetes therapy, albeit its translation has been impeded by incoherent graft performance. The use of decellularized ECM has lately gained substantial research momentum due to its innate capacity to augment the function of cells originating from the same tissue type. In the present study, the advantages of both these approaches are leveraged in a porcine pancreatic ECM (pECM)-based microencapsulation platform, thus significantly enhancing murine pancreatic islet performance. pECM-encapsulated islets sustain high insulin secretion levels in vitro, surpassing those of islets encapsulated in conventional alginate microcapsules. Moreover, pECM-encapsulated islet cells proliferate and produce an enriched intra-islet ECM framework, displaying a distinctive structural rearrangement. The beneficial effect of pECM encapsulation is further reinforced by the temporary protection against cytokine-induced cytotoxicity. In-vivo, this platform significantly improves glucose tolerance and achieves glycemic correction in 100% of immunocompetent diabetic mice without any immunosuppression, compared to only 50% mice achieved glycemic correction by alginate encapsulation. Altogether, the results presented herein reveal that pECM-based microencapsulation offers a natural pancreatic niche that can restore the function of isolated pancreatic islets and deliver them safely, avoiding the need for immunosuppression. STATEMENT OF SIGNIFICANCE: Aiming to improve pancreatic islet transplantation outcomes in diabetic patients, we developed a microencapsulation platform based on pancreatic extracellular matrix (pECM). In these microcapsules the islets are entrapped within a pECM hydrogel that mimics the natural pancreatic microenvironment. We show that pECM encapsulation supports the islets' viability and function in culture, and provides temporal protection against cytokine-induced stress. In a diabetic mouse model, pECM encapsulation significantly improved glucose tolerance and achieved glycemic correction without any immunosuppression. These results reveal the potential of pECM encapsulation as a viable treatment for diabetes, providing a solid scientific basis for more advanced preclinical studies.

A Bioartificial Pancreas with "Immune Stealth" and Continuous Oxygen Supply for Islet Transplantation.

Transplantation of microencapsulated islet cells remains a promising strategy for the normalization of glucose metabolism control in type 1 diabetes mellitus. However, vigorous host immunologic rejection, fibrotic overgrowth around the microcapsules, and poor oxygen supply often lead to graft failure. Herein, a bioartificial pancreas is constructed, which incorporates the "stealth effect" based on polyethylene glycol copolymers and the high oxygen-carrying performance of fluorinated nanoparticles. Polycationic poly(l-lysine)-grafted-poly(ethylene glycol) is successfully coated on the surface of alginate microcapsules through electrostatic interaction, which can not only resist fibrinogen adhesion and avoid excessive fibrosis around the microcapsules but also isolate the host immune system from attacking, achieving a "stealth effect" of microencapsulated islet cells. Furthermore, the coloading of fluoride-based O2 nanocarriers gives them enhanced oxygen-carrying and continuous oxygen supply capabilities, thereby effectively prolonging the survival of islet cells. The intracapsular islet cells still display similar cell viability and almost normal insulin secretion function even in long-term culture under hypoxic conditions. Collectively, here a new approach is opened for microencapsulated islets to efficiently evade host immune attack and improve oxygen supply and a promising strategy is provided for islet transplantation in type 1 diabetes mellitus.

Necrostatin-1 releasing nanoparticles: In vitro and in vivo efficacy for supporting immunoisolated islet transplantation outcomes.

Immunoisolation of pancreatic islets in alginate microcapsules allows for transplantation in the absence of immunosuppression but graft survival time is still limited. This limited graft survival is caused by a combination of tissue responses to the encapsulating biomaterial and islets. A significant loss of islet cells occurs in the immediate period after transplantation and is caused by a high susceptibility of islet cells to inflammatory stress during this period. Here we investigated whether necrostatin-1 (Nec-1), a necroptosis inhibitor, can reduce the loss of islet cells under stress in vitro and in vivo. To this end, we developed a Nec-1 controlled-release system using poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) as the application of Nec-1 in vivo is limited by low stability and possible side effects. The PLGA NPs stably released Nec-1 for 6 days in vitro and protected beta cells against hypoxia-induced cell death in vitro. Treatment with these Nec-1 NPs at days 0, 6, and 12 post-islet transplantation in streptozotocin-diabetic mice confirmed the absence of side effects as graft survival was similar in encapsulated islet grafts in the absence and presence of Nec-1. However, we found no further prolongation of graft survival of encapsulated grafts which might be explained by the high biocompatibility of the alginate encapsulation system that provoked a very mild tissue response. We expect that the Nec-1-releasing NPs could find application to immunoisolation systems that elicit stronger inflammatory responses, such as macrodevices and vasculogenic biomaterials.

Bacterial Viability in Self-Healing Concrete: A Case Study of Non-Ureolytic Bacillus Species.

Cracking is an inevitable feature of concrete, typically leading to corrosion of the embedded steel reinforcement and massive deterioration because of the freezing-thawing cycles. Different means have been proposed to increase the serviceability performance of cracked concrete structures. This case study deals with bacteria encapsulated in cementitious materials to "heal" cracks. Such a biological self-healing system requires preserving the bacteria's viability in the cement matrix. Many embedded bacterial spores are damaged during concrete curing, drastically reducing efficiency. This study investigates the viability of commonly used non-ureolytic bacterial spores when immobilized in calcium alginate microcapsules within self-healing cementitious composites. Three Bacillus species were used in this study, i.e., B. pseudofirmus, B. cohnii, and B. halodurans. B. pseudofirmus demonstrated the best mineralization activity; a sufficient number of bacterial spores remained viable after the encapsulation. B. pseudofirmus and B. halodurans spores retained the highest viability after incorporating the microcapsules into the cement paste, while B. halodurans spores retained the highest viability in the mortar. Cracks with a width of about 0.13 mm were filled with bacterial calcium carbonate within 14 to 28 days, depending on the type of bacteria. Larger cracks were not healed entirely. B. pseudofirmus had the highest efficiency, with a healing coefficient of 0.497 after 56 days. This study also revealed the essential role of the cement hydration temperature on bacterial viability. Thus, further studies should optimize the content of bacteria and nutrients in the microcapsule structure.

Investigation of encapsulation of pancreatic beta cells and curcumin within alginate microcapsules

AbstractCell encapsulation is an ideal approach for the replacement of pancreatic function in Type 1 diabetes. Poor biocompatibility of microcapsules generates an inflammatory response in the implantation site and induces fibrosis infiltration, which causes microencapsulated cell death and graft failure. To prevent inflammation after implantation, composite microcapsules that exhibit anti‐inflammatory properties were designed. This study is about encapsulating beta cells and curcumin within 1.5% alginate by the jet‐breaking regime of the syringe pump. The microcapsules’ size distribution and rate of the alginate solution were characterized to find uniform particles. Micro‐size particles were attained at a rate of 25 mL/min. Uniform spherical microcapsules (200–300 μm) were created in large amounts in a short period. Microcapsule breakage was less than 3% during 7 days, which demonstrated the stability of the encapsulation method. Insulin secretion and cell viability assays were performed 1, 3, and 7 days after microencapsulation by glucose‐stimulated insulin secretion (GSIS) and 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide (MTT) assays. No significant differences in the amount of insulin secretion and beta cell viability were observed among free cells, alginate microcapsules, and curcumin‐alginate microcapsules during 7 days (p &gt; 0.05). Therefore, the curcumin and alginate membrane did not show any harmful impacts on the function and survival of the beta cells.

A Multiple Unit Abuse-deterrent Dosage Form Based on Sodium Alginate

Abstract There are several approaches for the formulation of abuse-deterrent, tamper-resistant, or alcohol-resistant dosage forms. This work is specifically focused on the formulation of microforms and multiple unit dosage forms with the mentioned resistant features. We prepared microcapsules based on sodium alginate by Ca2+-induced gelation, containing caffeine as a model drug. The prepared microcapsules were dried either by hot air or freeze-dried and the resistance in an alcoholic environment and the resistance against mechanical stress were observed. Subsequently, swelling studies were conducted to predict the behavior of prepared microcapsules during dissolution testing. Differences in the behavior of microcapsules during dissolution testing were strongly related to the different abilities of Ca2+-alginate microcapsules to swell in an acidic and alkaline environment. Alginate microcapsules exhibited gastro-resistant properties due to excellent swelling in an alkaline environment and poor swelling in a gastric environment. The addition of ethanol did not influence the swelling behavior of alginate microcapsules in the gastric fluid; rather, it showed the opposite effect, where swelling was slightly suppressed. Therefore, we conclude that alginate microcapsules are alcohol resistant. Also, they showed high mechanical strength, and therefore, grinding the microcapsules into a powder was impossible.

Protective Effect of Alginate Microcapsules with Different Rheological Behavior on Lactiplantibacillus plantarum 299v.

Alginate encapsulation is a well-known technique used to protect microorganisms from adverse conditions. However, it is also known that the viscosity of the alginate is dependent on its composition and degree of polymerization and that thermal treatments, such as pasteurization and sterilization, can affect the structure of the polymer and decrease its protection efficiency. The goal of this study was to evaluate the protective effect of encapsulation, using alginates of different viscosities treated at different temperatures, on Lactiplantibacillus plantarum 299v under in vitro gastrointestinal conditions and cold storage at 4 °C and -15 °C, respectively. Steady- and dynamic-shear rheological tests were used to characterize the polymers. Thermal treatments profoundly affected the rheological characteristics of alginates with high and low viscosity. However, the solutions and gels of the low-viscosity alginate were more affected at a temperature of 117 °C. The capsules elaborated with high-viscosity alginate solution and pasteurized at 63 °C for 30 min provided better protection to the cells of L. plantarum 299v under simulated gastrointestinal and cold storage conditions.

Antiproliferative and Apoptotic Effects of Olive Leaf Extract Microcapsules on MCF-7 and A549 Cancer Cells.

Alginate microcapsules are a talented means for the delivery of broad curative biomacromolecules. In this study, we immobilized olive leaf extract (OLE) by calcium alginate (CA) and chitosan-coated CA (CCA) and characterized the OLE-loaded CA and CCA. The cytotoxic effect, the cell cycle arrest, and the apoptotic effect of OLE and its microcapsules were investigated against breast adenocarcinoma (MCF-7) and lung carcinoma (A549). As a result, the loading capacity of OLE-CA and OLE-CCA was found to be 80 and 99%, respectively, in optimal conditions. Also, OLE-CA and OLE-CCA were characterized by unique FTIR peaks and morphological display relative to the empty CCA microcapsules. The cytotoxicity analysis showed that the IC50 values of OLE-CA and OLE-CCA were determined to be 312 and 0.94 μg mL-1 against A549, respectively, whereas these were found to be 865.4 and 425.5 μg mL-1 for MCF-7 cells. On the other hand, the OLE microcapsules did not possess in any concentration of cytotoxic influence on the BEAS 2B healthy cell line. Also, the exposure of OLE-CCA to MCF-7 and A549 resulted in the arrest of more MCF-7 and A549 cells at the G0/G1 phase compared to the OLE. A549 and MCF-7 cells were predominantly found in the late apoptosis phase and necrosis phase, respectively. Optical microscopy images confirmed that OLE microcapsules were more effective against MCF-7 and A549 than free OLE. The present work suggested that the OLE microcapsules might be administered as nutrition supplements for cancer therapy.